Liquid feeding apparatus



Feb. 12, 1946. R H; DARD 2,394,852

LIQUID FEEDING APPARATUS Filed Aug. 29, 1940 2 Sheets-Sheet l Feb. 12, 1946. GODDARD 2,394,852

LIQUID FEEDING APiARATUS 2 Sheets-Sheet 2 Filed Aug. 29, 1940 Patented Feb. 12, 1946 UNITED STATES PATIENT OFFICE,

LIQUID FEEDING APPARATUS Robert H. Goddard, Roswell, N. Mex., assignor of one-half to The Daniel and Florence Guggenheim Foundation, New York, N. Y., a corporation of New-York Application August 29, 1940, Serial No. 354,761

' 19 Claims. (01. 222,-94)

This invention relates to apparatus adapted to feed liquids by gas pressure. One important use of my invention is in connection with rocket craft or other air-craft in which two liquids,

such as gasoline and liquid oxygen, are to be fed .at high pressure to a combustion chamber.

It is the general object of my invention to provide improved liquid-feeding apparatus for such use and for other similar purposes, which apparatus is extremely light in weight and which will supply two or more different liquids under pressure in a safe and reliable manner. I further provide improved means by which a substantially constant gas pressure may be maintained as the tanks are gradually emptied.

More specifically, my invention relates'to the provision of liquid feeding apparatus comprising alight but strong and rigid outer metal casing and a plurality of flexible and collapsible inner tanks which are enclosed by said outer casing and which are adapted to store and deliver for producing gas pressure.

Under the previous practice, where two liq -uids, such as gasoline and liquid oxygen, were to be fed under pressure, it was customary to provide separate tanks for the gasoline and for the oxygen, and also to provide a third tankcontaining compressed air-or other gas to supply different kinds of liquids, such as gasoline and liquid oxygen.

I also provide means for ejectingthe liquids from the inner tanks by gas pressure exerted on the outside of said tanks, which gas pressure .may be much higher than could be previously used in direct contact with cold liquids. Another feature of the invention relates to means for precooling the oxygen tank and its connections before the tanks are filled.

My invention further relates to arrangements and combinations of parts which will be here inafter described and more particularly pointed out in the appended claims.

A preferred form of the invention is shown in the drawings, in'which:

Figure 1 is a sectional elevation of my improved pressure tanks;

Figs. 2 and 3 are sectional plan views, taken along the lines 22 and 3-3 in Fig. 1 respectively;

Fig. 4 is an enlarged side elevation, partly in section, of the lower end of a gas generator;

' to be described;

the necessary pressure to feed the liquids.

By my present invention, I very much simplify and lighten this previous construction, as well as providing a substantial saving in space, which is all very desirable in any aircraft.

My improved pressure apparatus in its preferred form comprises an outer sheet metal casing 20 (Fig. 1), preferably of cylindrical form and with hemispherical ends. The walls of this casing should be of light but strong metal and may be wire-bound for increased strength, as disclosed in my prior Patent No. 2,109,529.

Within the outer casing 20 I provide two inner flexible tanks or containers 2| and 22 (Figs. 2 and 8) of'semi-cylindrical shape and rounded ends, and substantially filling the casing 20 when fully extended. The fiat adjacent walls 23 of the tanks 2| and 22 are concavely recessed, as indicated at 24 (Figs. 2 and 8) for a purpose to be described.

Gasoline is admitted to the tank 2| through a' filling pipe 25 (Fig. 1) at the lower end thereof, and a vent pipe 26 is connected to the upper end of the tank 2|. The tank 22 is similarly provided with a filling pipe 21 and a vent pipe 28.

. It will be noted that the vent pipe 28 for the oxygen talk 22' is substantially larger than the feed pipe 21, to allow easy escape of any oxygen evaporated in cooling the metallic wall of the tank 22 as the tank is being filled.

Provision is made for attaching a hose, as 30, to each of the pipes 25 to 2.8, and a flap valve 3| is provided in eachof the pipes. These valves are arranged to close outwardly and each valve isopened inwardly by a projecting member 32 (Fig. 1) when a hose is attached thereto for filling the tank. The liquid contents of the 'tanks 2| and 22 are ejected by gas pressure exerted between the casing 20 and the outer surfaces of the tanks 2| and 22. I

I preferably form the gasoline tank 2| of the flexible material shown in Fig. 5, which comprises an impervious outer layer 33 of a light soft metal, such as an annealed aluminum alloy, and an inner layer of wire cloth 34, secured at spaced points to the layer 33, as by spot welding. The

stiffness of the wire cloth prevents the formation of sharp folds or creases in the light soft sheet metal, yet at the same time the fabric is extremely light.

The fabric used for the liquid oxygen tank 22 is of somewhat different construction, due to problems arising from the extreme coldness of the oxygen. I I

I preferably provide a fabric for the oxygen tank 22 which comprises a thin soft metal liner 35, a loosely knitted net fabric 31, preferably of woolen thread, a layer of wire cloth 38, and an outer layer of cloth 39. The knots and threads of the net layer 31 separate the inner wall 36 from the wire cloth 38. The outer cloth layer 39 is preferably treated to make it air-tight.

Outside pressure againstthe tank presses the cloth 39 against the wire cloth 38, which in turn is pressed against the net 31 and metal inner wall or liner 35. It is not necessary to otherwise secure these layers together.

The cloth 39 and net 31 greatly reduce heat transfer through the adjacent walls of the tanks 2| and 22. Freezing of gasoline in the tank 2| is thus avoided, unless the tank 22 is filled too long before the apparatus is to be used.

The cloth 39 and net 31 also prevent rapid cooling of the gas in the casing 2|), which gas provides pressure to eject the liquids from. the tanks 2| and 22. Such insulation is very important, as any gas exposed to liquid oxygen or to surfaces directly cooled thereby will be lowered in pressure or actually condensed, and the maintenance of high and uniform gas pressure is extremely difilcult.

The small mass of metal in the fabric of the oxygen tank 22 reduces the tendency to develop gas bind during filling. It will be obvious that one or more of the layers shown in Figs. 5 and 6 may be duplicated, where a stronger or heavier flexible tank is required. Perforated bafiie plates 40 of thin soft metal may be provided in the tanks 2| and 22 and will be secured to the outer walls thereof, to prevent excessive agitation.

Gasoline is delivered from the tank'2l to a combustion chamber (not shown) through a pipe 40 (Fig. 1) which is connected to a perforated tube 4| extending upward through the tank 2| and secured in the outer casing 20. A similar pipe 42 and perforated tube 43 is provided for the oxygen tank 22. The perforations 44 (Fig. 9) in the tubes 4| and 43 are covered by a layer of wire cloth 45 which prevents the flexible material of the tanks from being caught or torn on the edges of the perforations. r

The tubes 4| and 43 not only provide for delivery of the liquids from the tanks but also provide supports on which the upper ends of the tanks 2| and 22 are slidable as the tanks are deflated. At the same time, the tubes prevent any premature restrictive collapse of the lower portions of the tanks which might otherwise occur.

Gas to provide pressure to deflate the tanks 2| and 22 is developed in a gas generator 50 (Figs. 1 and 4) mounted in the lower part of the casing 28 and delivering gas to the top of the casing 20 through a pipe 50 disposed in the tank recesses 24. Gasoline enters the generator 5|] through a tangential feed pipe 5| and liquid oxygen through an axial spray pipe 52. The general construction is similar to that shown in my copending application Serial No. 310,613 but shown herein in inverted position. For starting combustion, an igniter 53 is provided, which in its simplest form, may contain a powder 54 (Fig. 4) fired by a fuse wire 55.

In order to provide simple means for feeding gasoline and liquid oxygen to the generator 50, I enclose a separate power-operated pressure unit in each of the tanks 2| and 22. One of these units is shown somewhat diagrammatically in Fig. 11 and more in detail in Fig. 10.

Referring to Fig. 11, I provide for each tank a power bellows 68, mounted at the' top of the casing 20 and having its open inner surface exposed to atmospheric pressure. for the gasoline tank 2| is mounted at the upper end of the perforated tube 4|, so that the outer surface of the bellows 60 is exposed to the liquid pressure in the tank 2|, which corresponds to the pressure exerted thereon by the gas in the easing 20.

The lower end of the power bellows is connected by a rod 62 (Fig. 11) to a cross head 63, slidable in slots in the tube 4| and connected at each end bya link 64 to a member 65, to which a bottom plate 66 is connected by rods 61. Each bottom plate 66 forms the movable end of a col- I to the gasoline feed pipe (Fig. 4) in the gas generator 50.

In order to fill the pumping device with gasoline as the tank 2| is being filled, it is necessary to provide an admission valve (Fig. 10) at the bottom and a vent valve 16 at the top. These valves have outward closing movement under the influence of springs 11 and 18 respectively and are normally closed.

It is necessary, however, that these valves be held open during the filling of the gasoline tank 2|, and for this purpose I provide levers 83 and 8| which engage the valve rods of the valves 15 and 16 respectively. At their outer ends, they are connected to a rod 82 which extends outward through the casing and is connected at its outer end to a manually operated lever 83. By moving the lever 83, the valves '15 and 16 may be forced open or may be released for spring closing.

In order to avoid leakage, the rod 82 (Fig. 10) passes outward through a bellows packing 84 having its head 85 secured to the rod 82; A washer 86 on the rod 82 closes the inner end of the bellows packing 84 when the rod is depressed to permit spring closing of the valves I5 and 16, This makes possible the use of a very thin, flexible bellows 84, since the washer 8B acts as a valve, and prevents the pressure in 2.0 from entering the bellows, during operation.

The top position of the power bellows for the oxygen feed is important, as it might become more or less filled with liquid oxygen if below The bellows 60 I02 will be depressed, allowing the valve I to As the operating pressure on the power bellows 60 is higher than the pressure in the pumping devices I0, the bellows 60 may be of substantially smaller size.

In order to hold the collapsible pumping device I0 open during the filling of the gasoline tank,

the movable lower plate 66 is provided with a notched stud 90 (Figs. and 10) engaged by a latch lever 9|, which in turn is engaged by the double pumping device and its operating connections to avoid tearing the tanks 2| or 22. The perforations are protected by wire cloth.

The construction and operation of the pumping devices in the oxygen tank 22 are the same as described for the gasoline tank 2|.

In order to provide a certain initial pumping pressure before gas pressure is developed in the generator 50, I provide tension coil springs93 in the tubes 4| and 42, which springs surround the rods 62 to which the power bellows 60 are connected. The lower end of each tension spring 93 is connected to a cross head 63, and the upper end is connected to a fixed point in one of the tubes 4| or 42.

Consequently a certain minimum pressure is developed to feed gasoline and oxygen .to the gas generator 50 as soon as the bottom plates 66 are released by the latch levers 9|. While this pressure is not sufficient for continuous operation and would progressively decrease, it is nevertheless suflicient to start the gas generator;

As soon as the gas generator 50 is rendered operative bythis initial feeding of small portions of gasoline and oxygen on release of the bottom plates andbegins to generate gas, the pressure within the casing 20 begins to rise and this pressure is communicated through the flexible containers 2| and 22 and the perforated tubes 4| and 43 to the enclosed spaces around the outside of the power bellows 60. This causes the bellows 60 to collapse, pulling upward on the rod 62 and acting through the mechanism shown in Figs. 10 t and 11 to fully deflate the pumping devices 10.

The liquids contained in the pumping devices are thereupon ejected into the generator 50 and thus provide enough pressure to fully deflate the containers 2| and 22. The pumping devices I0 thereafter remain inactive until the containers 2| and 22 are refilled, at which time the pumping devices I0 are also refilled as previously described.

Two pumping devices I0 are provided for ,each

tank 2| and 22, as shown in Fig. 3, it being desirable to use two bellowsof smaller diameter rather than a substantially larger single bellows,

as an increased diameter of the gas generator 50 is thereby made possible.

In order to control and regulate the gas presclose. As the pressure in the casing 20 decreases.-

the rod I02 will rise, opening the valve I00. In

this way the gasoline feed will be varied inversely in accordance with changes in pressure in the casing 20. A similar pressure regulator is provided for the oxygen feed. Without such regulation, the feed would progressively increase, as the power bellows 60 would be directly responsive to increased gas pressure in the casing 20.

It is desirable that the regulatingvalve I00 remain closed during the filling of the tank 2|, and it is therefore necessary to mechanically withdraw the rod I02. For this purpose, I. provide a lever I05 pivoted at I06 to the open tube surrounding the bellows member I03. One end of the lever I05 is hooked to the outer end of the rod I02, and the other end of the lever 'is con nected to a link I08 which extends upward into a fixed block I09 and which is provided with an eye to receive the end of a latch rod H0.

The rod H0 is connected to the up-turned end III (Fig. 10) of the manually operated lever 83 previously described. When the lever 83 is depressed to free the valves": and i6 and release the movable bottom plate 66, the pull rod H0 is withdrawn to release the link I08 and free the regulating rod I02.

The disc valves used to close the feed pipes 40 and 42 during tank filling are of the special construction shown in Figs. 13 to 16'inclusive, which construction involves no moving parts.

Each valve comprises a very thincircular disc I20 of soft metal and a slotted disc I2I of a harder metal. A strainer I22 of wire cloth'faced by a perforated disc I23 is also provided. These parts are assembled between spaced flanges I25 in the pipes 40 or 42, with the slotted disc I2I er I22 and perforateddisc I23 spaced substantially below'the soft metal disc I20. The slotted sure in the casing 20, I provide regulators for the gasoline feed and the liquid oxygen feed to the generator 50. Such a regulator for the gasoline feed is shown in Fig. 12.

A valve I00-is interposed between the gasoline feed pipes I3 and 5| of the generator 50 and is normally closed by a spring IOI. A rod I02 is connected to the outer end of a bellows member I03 mounted in an'open tube on the casing 20 and exposed at its inside to the gas pressure in the casing. The member I03 is normally contracted. As the gas pressure increases, the rod disc I2| is fastened to the .disc I20, as by soldering, preferably along the edges of the slot in order not to reduce flexibility. When pressure is applied, the disc I20 isruptured or broken along the slotted lines in the disc I2I, and any small fragments of the ruptured disc are retainedv by the strainer I22 and perforated disc I23, so that they cannot pass into the combustion chamber, or other device, which is being supplied with liquids. be torn away because of the connection of the disc I20 with the disc I2I.

It is desirable to cool the oxygen feed pipe 42 (Figs. 1 and 13) below the disc valves I20 therein, to avoid gas bind, and for this purpose I provide a cooling jacket I30 surrounding the disc valve casing and the lower end of the perforated tube 43. A pipe I32 (Fig. 17) extends from the upper end of the jacket I30 through the casing 20 and through the lower end wall of the oxygen tank 22. The inner end of this pipe I32 is closed by a manually operated valve I33 secured at thev inner end of a valve rod I34 which extends out through a bellows packing I35 and is provided with a sealing washer I36, all as previously de-- No large fragments of the disc I20 can surface of the tank 22.

.cooled by the initial low temperature of the Q with possible freezing of the rather closely adjacent gasoline. The pro-cooling means comprises a spray nozzle I40 (Fig. '7) projecting inside the hose attached to the oxygen filling pipe- '21. ,oxygen to the nozzle I40 when desired, and fine A manually controlled valve admits liquid drops of the cold liquid engage the whole inner The tank is quickly if cooled by expansion or evaporation, is warmed I by the generator. gases before entering the casing 20.

The pressure under which the liquids are delivered from the pipes 40 and 42 may be varied by adjusting the springs IOI (Fig. 12) in the pressure regulating devices which control the flow of gasoline and oxygen to the gas generator 50. A similar adjustment may be made for the auxiliary pressure tank I50 (Fig. 18). These adjustments may be made manually or by suitable automatic or timing devices.

From the foregoing description, the general method of operation will be readily understood. The levers 83 (Fig. 10) are first set to open the valves 15 and I6 for each pumping device, and the rods I02 (Fig. 12) are drawn down and locked by the pull rods H to permit the valves IOI in the pressure regulators to close. Liquid oxygen for precooling is admitted through the spray nozzle I40 (Fig. 7) and through the pipe I32 (Fig. 17) to the pre-cooling jacket I30 (Fig. 13). Unbroken discs I20 are inserted in the disc valves in the delivery pipes 40 and 42 (Fig. 13). The

tanks 2| and 22 and the pumping devices 10 (Fig. 10) are then filled and the apparatus is ready for use. The levers 83 are moved to close the valves I5 and I6 and to release the valveopening rods I02. The springs 93 (Figs. 1 and 10) then start delivery of gasoline and oxygen to the gas generator 50 and combustion is initiated by the igniter 53 (Fig. 4) As soon as initial pressure is generated, the power bellows 60 actuate the pumping devices 10 under control of the pressure regulatingvalves I00 (Fig. 12). 1

The regulated gas pressure thus produced acts against the flexible walls of the tanks 2| and 22 to rupture the valve discs I20 and force gasoline and liquid oxygen out of the pipes 40 and 42 to the combustion chamber of a rocket craft or for other desired uses. This operation will then continue until the liquids are exhausted in the tanks 2i and 22.

.The almost complete absence of moving parts is a particular advantage of my invention and is extremely important when extremely cold liquids are to be delivered.

Having thus described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what I claim is:

1. Liquid feeding apparatus comprising ai rigid outer casing, a plurality of flexible liquid containers in said casing, separate filling discharge and vent connections for each container effective casing to collapse said containers substantially radially and toward each other.

2-. Liquid feeding apparatus comprising a rigid cylindrical outer casing with rounded ends, two

semicylindrical flexible containers substantially filling said outer casing when distended, separate discharge outlets for said containers through said outer casing, and means to apply gas under pressure within said casing to simultaneously deflate and discharge both of said containers.

3. Liquid feeding apparatus comprisinga rigid outer casing, a plurality of flexible liquid containers in said casing, separate discharge connections from said containers, meansv to apply gas under pressure between said containers and said outer casing, and means to generate said gas within said casing by commingling and igniting small portions of the contents of said liquid containers.

4. Liquid feeding apparatus comprising a rigid outer casing, a plurality of flexible liquid containers in said casing, separate discharge connections from said containers, means to apply gas under pressure between said containers and said outer casing, and means to generate said gas within-said casing by combustion of liquid supplied from said containers.

5. Liquid feeding apparatus comprising a rigid outer casing, a plurality of flexible liquid containers insaid casing, separate discharge connections from said containers, means to apply gas under pressure between said containers and said outer casing, a gas generator within said casing, and means to feed liquid fuel and a liquid oxydizing agent from said containers to said enerator.

6. Liquid feeding apparatus comprising a rigid outer casing, a plurality of flexible liquid containers in said casing, separate discharge connections from said containers, means to apply gas under pressure between said containers and said outer casing to collapse said containers and thereby discharge the contents thereof through said discharge connections, an inwardly opening filling valve for each container, and an inwardly open and after the filling of said containers and devices.

9. Liquid feeding apparatus comprising a rigid outer casing, flexible liquid containers in said casing, a gas generator in said casing, a,

pumping device in each container to deliver liquid from said container to said generator, and a power bellows connected to operate said pumping device by gas pressure developed in said generator.

10. Liquid feeding apparatus comprising a rigid outer casing, flexible liquid containers in said casing, a gas generator in said casing, a pumping device in each container to deliver liquid from said container to said generator.

and means to limit the flow of liquids from said containers to said generator to such amounts as will produce a substantially constant gas pressure'in said outer casing.

11. Liquid feeding apparatus comprising a rigid outer casing, flexible liquid containers in said casing, a gas generator in said casing, a pumping device in each container to deliver liquid from said container to said generator, and a pressure regulator for each container which controls the flow of liquid from said container to said generator and thereby maintains substantially constant gas pressure in said outer casting.

12. Liquid feeding apparatus comprising a rigid outer casing, flexible liquid containers in said casing, a gas generator in said casing, a pumping device in each container to deliver liquid from said container to said generator, means to deflate said pumping device to. eject liquid therefrom to said generator, and means to lock said device in distended position during the filling of said container and pumping device.

13. Liquid feeding apparatus comprising a' rigid outer casing, flexible liquid containers in said casing, a gas generator in said casing, a.

pumping device in each container to deliver liquid from said container to said generator, a filling valve and a vent valve for each pumping device, means to lock the pumping device in distended condition, means to hold said valves open during the filling of said container and pumping device, and means tosimultaneously close said valves and unlock said pumping device after filling is completed.

14. Liquid feeding apparatus comprising a rigid outer casing, flexibleliquid containers in said casing, a 'gasgeneratorin said casing, a pumping device in each container to deliver liquid from said container to said generator, a power bellows connected to operate each pumping device by gas pressure developed in said generator, and spring means to operate said pumping devices before gas in produced in said generator.

15. Liquid feeding apparatus comprising a rigid cylindrical outer casing with rounded ends, two semi-cylindrical flexible containers substantially filling said outer casing when distended, separate discharge outlets for said containers through said outer casing, means to apply gas under pressure within said casing to deflate said containers, and a device extending longitudinally through each flexible container and effective to prevent restrictive collapse of said container.

16. In a liquid feeding apparatus, a flexible container, a discharge connection therefrom, a tube extending through said container from said discharge connectionand having perforations opening within said container, and a wire cloth covering for said tube and perforations.

17. In a liquid feeding apparatus, a rigid outer casing, flexible containers in said casing for gasoline and liquid oxygen, a gas generator in said casing, a pumping device in each container to deliver liquid from said container to said generator, means to fill said containers and pumping devices, and means to lock each pumping device in distended position during the filling of said container and pumping device.

18. In a liquid feeding apparatus, a rigid outer casing, a flexible container for liquid oxygen in said casing, a gas generator in said casing, a pumping device in said container to deliver liquid oxygen from said container to said generator, and means to precool the discharge connections from said oxygen container before any liquid oxygen is ejected therethrough.

19. In a liquid feeding apparatus, a rigid outer casing, a flexible storage receptacle in said casing for a very cold liquid, means to flll said. receptacle with said liquid,'and means to initially spray the inner surface of said flexible receptacle with a portion of said liquid to precool said inner surface and to thereby prevent evaporation of said cold liquid and resultant gas-bind during the ensuing filling operation.

ROBERT GODDARD. 

